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Summary of Significant Accounting Policies (Self Insurance Retention Liability (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2016
Self insurance Retention Liability [Line Items] |  |
Self insurance retention liability | $ 3.0 | $ 2.0
Self insurance retention liability aggregate | 6.0 |
Self insurance retention liability additional deductible | 5.0 |
Self insurance retention Workers' compensation | 1.0 |
Letters of credit outstanding, amount | 30.3 |
Minimum |  |
Self insurance Retention Liability [Line Items] |  |
Self insurance retention aggregate deductible applicable range | 3.0 |
Self insurance retention liability additional deductible applicable range | 5.0 |
Maximum |  |
Self insurance Retention Liability [Line Items] |  |
Self insurance retention aggregate deductible applicable range | 5.0 |
Self insurance retention liability additional deductible applicable range | 10.0 |
State of Nebraska [Member] |  |
Self insurance Retention Liability [Line Items] |  |
Workers' compensation insurance bonds | 26.7 |
Workers compensation insurance carrier [Member] |  |
Self insurance Retention Liability [Line Items] |  |
Workers' compensation insurance bonds | $ 6.9 |

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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. + References No definition available. + Details
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X
- Definition The disclosure indicates the applicable range for aggregate liability retained by the company (self-insured retention and deductible) for each bodily injury or property damage occurrence between $3.0 million and $5.0 million. + References No definition available. + Details
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- Definition The disclosure indicates the amount of liability retained by the company (self-insured retention and deductible) for each bodily injury or property damage occurrence. + References No definition available. + Details
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X
- Definition The disclosure indicates the amount of additional liability retained by the company (self-insured retention and deductible) for each bodily injury or property damage occurrence between $5.0 million and $10.0 million. + References No definition available. + Details
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X
- Definition The disclosure indicates the applicable range for additional liability retained by the company (self-insured retention and deductible) for each bodily injury or property damage occurrence between $5.0 million and $10.0 million. + References No definition available. + Details
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X
- Definition The disclosure indicates the amount of liability retained by the company (self-insured retention) for each workers' compensation occurrence. + References No definition available. + Details
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- Definition The disclosure indicates the annual aggregate amount of liability retained by the company (self-insured retention and deductible) for claims between $3.0 million and $5.0 million. + References No definition available. + Details
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- Definition The disclosure indicates the amount of the bonds carried for workers' compensation insurance. + References No definition available. + Details
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Balance Type: | debit
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- Details
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- Details
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Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |